High voltage system equipment such as a battery (power equipment), an inverter (a power converter), or an ECU (a controller) is mounted in a vehicle such as a hybrid vehicle that travels with a combination of an engine and a motor, an electric vehicle that travels using a motor alone, or the like. These pieces of high voltage system equipment are electrically connected via high voltage wiring (a harness). The high voltage wiring is preferably protected using a harness holder to avoid damage (e.g., see WO2015/056551).
In the related art, however, the harness holder includes a holder main body whose upper portion is open, and a holder cover that covers the upper portion of the holder main body. Since the surroundings of the high voltage wiring housed in the harness holder are merely covered by the holder main body and the holder cover, when the harness holder receives a great shock in the event of vehicle collision, a function of protecting the high voltage wiring may be damaged. For example, when the harness holder is disposed below a seat rail for a seat, the seat rail may enter the harness holder in the event of vehicle collision so that the high voltage wiring is damaged.